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221 Uppsatser om Nitrogen fixation - Sida 8 av 15

Strötorvsanvändning i djurstallar : en litteraturgenomgång

Peat litter has been used in animal houses for a long time. Because of its good ability to absorb liquid and nutrients from the manure it can create a dry surface for animals and a valuable manure product. Through changes in agricultural practises the use of peat litter has diminished and is to a great extent replaced by straw, sawdust and cutter shavings although Sweden is rich in peat-findings. The aim of this work was to summarize the presented knowledge about the used of peat litter, techniques, advantages and disadvantages and to compare with other commonly used litter materials. Articles on peat litter have been searched for in magazines, databases and books at SLU library. Visits to peat industries, interviews with peat producers and with peat researchers contributed to the material. Peat is not a uniformly material.

Kväveläckage inom Tolångaåns dräneringsområde : modellering och åtgärdssimulering

Under de senaste 300 åren har jordbrukslandskapet i Sverige genomgått stora förändringar. I början av 1900-talet introducerades konstgödslet och efter andra världskriget ökade gödslingen dramatiskt i syfte att maximera produktionen. Detta har lett till att överskottet av kväve har spolats ut i vattendragen. I detta arbete har stor vikt lagts vid att skapa en egen kvävemodell i syfte att simulera kväveläckaget från jordbruksmarken i Tolångaåns dräneringsområde..

Impact of Eucalyptus plantations on pasture land on soil properties and carbon sequestration in Brazil

Soil organic carbon (SOC) stocks and fluxes in forest ecosystems are influenced by natural and human disturbances. In the tropical regions the highest impacts on disturbance in forest C cycles are related to human activities such as conversion of natural lands to cropland and pasture areas and to forest plantations. The disturbances in the forest C cycles will release CO2 emissions to the atmosphere triggering global warming. In this study the focus was set in subtropical soils in Brazil, south extreme region of Bahia. The aim of the study was to investigate whether reforestation of Eucalyptus plantations under former pasture areas will help mitigate climate change through carbon sequestration.

Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige

Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering.

Humankapitalets roll i kunskapsföretags förvärvsprocess

Syftet med uppsatsen är att beskriva och analysera ett antal kunskapsföretags värdering av humankapitalet vid tänkbara företagsförvärv. Syftet är även att beskriva Human Resources Due Diligence och diskutera om detta begrepp/förhållningssätt kan tillföra företagsvärdering något. Vi har använt oss av deduktiv metod för att dra våra slutsatser. Primärdatan har insamlats genom fallstudier, dessa fallstudierna har genomförts genom semistrukturerad intervjuform. Vi grundar vår uppsats på teorier kring kunskapsföretag, humankapital, förvärvsprocess samt begrepp som Due Diligence och Human Resources Due Diligence.

Att gestalta en socialt hållbar begravningsplats

This thesis aims to present the essential background on how to perform climate changeimpact assessments, and to present the results from a climate impact assessment on waterbalance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwesternSweden, grown with spring cereals. This study is meant to be a benchmark example,and cannot be seen as a regional or national assessment for Sweden, rather as an approachto present and analyze the most important parts of these kinds of assessments.A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for thisstudy. The model was parameterized and calibrated against data from an experimental site,located in Mellby in Hallands county, south western Sweden. Measurements were carriedout between 1st of April 1988 and 1st of April 1991.

Water balance and nitrate leaching from arable land in a changed climate : a model study

This thesis aims to present the essential background on how to perform climate changeimpact assessments, and to present the results from a climate impact assessment on waterbalance and nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwesternSweden, grown with spring cereals. This study is meant to be a benchmark example,and cannot be seen as a regional or national assessment for Sweden, rather as an approachto present and analyze the most important parts of these kinds of assessments.A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for thisstudy. The model was parameterized and calibrated against data from an experimental site,located in Mellby in Hallands county, south western Sweden. Measurements were carriedout between 1st of April 1988 and 1st of April 1991.

Tillförsel av använda fosforfilter påverkar inte tillväxten eller fosforupptaget hos korn

The eutrophication of inshore seas, lakes and watercourses is mainly due to leaching of nitrogen and phosphorus (P) from agriculture. Many efforts are made to reduce the lea-kage of phosphorus in Sweden and the Baltic Sea countries. Phosphorus is also a finite resource and the mining of good quality raw material gets more and more difficult. Se-dimentation dams in combination with filters is one relatively new method to separate P from run-off and drainage water from agricultural land. This study was a part of an IVL Swedish Environmental Research Institute?s project which tests the capacity and func-tion for separation of phosphorus in four phosphorus filters.

EN MILJ?STUDIE OM DE GEOKEMISKA F?RH?LLANDENA I SK?RHAMN, SVENSKA V?STKUSTEN

The following study aims to investigate the environmental conditions of the harbor of Sk?rhamn, a small fishing community on the west coast of Sweden. The interest to do so rose as a newly built apartment residence failed to connect the sewage pipes of 18 apartments, causing the untreated sewage running into the sea. The parameters accounted for are the C/N ratio, total organic carbon (TOC) as well as total nitrogen present (TN) and ?13C in the top ten centimeters of a sediment core retrieved in the Sk?rhamn harbour.

Something fishy in Christians : Dietrekonstruktioner genom analys av stabila isotoper på tidigmedeltida skelett från Rambodal, Styrstad Sn, Östergötland

Dietary patterns has varied throughout history, both due to resource and cultural limitations. In this thesis, a study was conducted to establish the dietary patterns of eight individuals from an early Midieaval gravesite in Rambodal, Östergötland, in order to explain why they were buried there. This was done through stable isotope analysis on collagen extracted from bone and tooth on the buried individuals. The analysis showed that these indviduals had a diet that was mainly based on freshwater fish. This suggests that these people may have been christians, due to the fact that fish was not regarded as meat and therefore you did not have to abstain from it during periods of fasting.

Nutritionens betydelse för akut traumatiskt hjärnskadade patienter

The aim of the literature review was to illuminate the importance of nutritional management to patients who have sustained a traumatic brain injury (TBI) and describe nurses responsibility and meaningful function in the nutritional support. TBI patients tend to be associated with hypermetabolism and hypercatabolism, resulting in negative nitrogen balances. The results reveal increased energy expenditure and assessments of needs energy requirements at the TBI patients. This study determining the route of feeding: enteral versus parenteral nutrition. Furthermore describes complications associated with enteral feeding.

Biogasanvändning vid Käppalaförbundets Reningsverk: ? en värdering av miljöeffekter

This thesis calculates and compares the values of improved environmental quality due to future possible investment alternatives in biogas production facilities at Käppalaförbundets Reningsverk (Käppala Sewage Treatment Works) in an attempt to determine which alternative yields the highest such value. Käppala faces three investment alternatives for the usage of biogas. The alternatives are production of vehicle fuel, district heating and thirdly, heat and power production. Estimates of the value of environmental change are calculated for each of the three investment alternatives, and these estimates are then compared. The environmental change in question is the change in discharge levels of carbon dioxide (CO2), nitrogen oxides (NOx), sulphur dioxide (SO2) and particle matter.

Kan kväve bevaras i dräneringsvatten från åkermarksom lagras i dammar? : ett laboratorieförsök

The aim of this thesis was to examine if it is possible to keep nitrogen in the form of nitrate(NO3-) in ponds from one season to another by keeping a high concentration of oxygen in thepond water. This hypothesis was tested by doing a lab experiment where two systems werecompared according to nitrate concentration. One system had high concentration of oxygen inthe water and one had low concentration of oxygen. Before the main experiment wasconducted I did a pilot study to test the system setup and included parameters. The result fromthis study and the main study did not show the same result.

Det sociala ansvaret i skapandet av skönhetsidealen

Kandidatarbetet undersöker och diskuterar frågeställningen "Vilket socialt ansvar har jag som grafisk formgivare i skapandet av skönhetsidealen?". Kandidatarbetet fokuserar på att skapa en diskussion kring ämnet skönhetsideal, hur dessa påverkar unga kvinnor samt vilka möjligheter det finns för att bryta samhällsnormer och göra en förändring, en större skillnad. Utifrån mitt forskringsresultatet kring skönhetshistorian och dess utveckling under åren, har jag skapat en produktion i form av modeillustrationer. Jag tycker inte att samhället inser hur kraftfullt påverkade vi har blivit av media och modebranschen under de senaste åren. Även de som inte är intresserade av mode och skönhet. Vi som jobbar inom medie- och reklambranschen är den tredje statsmakten.

Dygnsvariation av metanemission från en anlagd våtmark

The aim of the study was to investigate if methane emission in a constructed wetland changed in a diurnal pattern correlating to temperature, humidity or light conditions. The gas measurements were carried out with a static chamber technique. The wetland (in Nykvarn outside of Linköping, Sweden) takes care of wastewater to reduce the nitrogen loads. Measurements were carried out at three different occasions in the summer of 1998 on two sites in the wetland. One site was close to the inflow, inhabited by Lemnaceae, and another site was located further downstream inhabited by the emergent macrophyte Typha latifolia.

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